Hint: This gives me a sinking feeling
I’m not sure what happened with the position of the box installed for this fire alarm speaker/strobe. Was another layer of sheetrock added to the wall? Was the box originally set back too deep? Or was it something else? Whatever the reason might be, the end result is a violation of Sec. 314.20.
Installations in noncombustible walls are permitted to have the box set back no more than ¼ in. from the finished surface. This box is set back about an inch. That is too much. An extension ring, plaster ring or some other listed box extender could be installed to solve the problem here. Another more invasive option would be to rip the wall open and reposition the original box, so it complies with the ¼ in. set back. I think installing an extension ring may be the easiest solution here. FYI- Installations in combustible surfaces are not permitted to be set back at all from the finished surface.
